Proposal of a diagnostic algorithm for myofascial trigger points based on a multiple correspondence analysis of cross-sectional data.

BACKGROUND: Myofascial trigger points (MTrPS), the morphological correlate of myfascial pain syndromes (MPS), contribute to the worldwide high chronic pain burden. However, uncertainty about MTrP diagnostic criteria remains. Aim of this cross-sectional study was to characterize clusters of diagnostic criteria assessable during physical examination that might guide MTrP diagnosis. METHODS: Thirteen MTrP diagnostic criteria proposed in relevant literature were assessed by standardized examinations in the trapezius and levator scapulae muscles of 61 chronic pain patients undergoing an interdisciplinary pain assessment. Hierarchical cluster analysis from multiple correspondence analysis was applied to data of the four muscles separately. Examining physicians classified the findings as MTrP, sufficient for diagnosis of an MPS and/or relevant for the patients' pain condition. RESULTS: Taut bands, hypersensitive spots within a taut band, nodules within a taut band and referred pain (classical diagnostic criteria) were most frequent (28-66% M. trapezius, 8-21% M. levator scapulae). Restricted range of motion, pain during contraction, pain exacerbation during emotional stress, muscular weakness, jump sign, local twitch response and autonomic phenomena (complementary diagnostic criteria) occurred in 2-25% and hypersensitive spots and nodules outside of a taut band in 2-7% of the cases. Four clusters emerged: (1) no or just one diagnostic criterion, mostly a taut band alone; (2) a hypersensitive spot and/or nodule outside of a taut band partly in combination with complementary diagnostic criteria; (3) at least two classical diagnostic criteria (mostly a taut band containing a hypersensitive spot) partly in combination with complementary diagnostic criteria; (4) at least two, rather three, classical diagnostic criteria always in combination with complementary diagnostic criteria. Referred pain was specific to cluster 3 and 4. Among classical diagnostic criteria, palpable nodules within a taut band contributed least, and among complementary diagnostic criteria, restricted range of motion and pain during contraction contributed most to data representation. CONCLUSION: We propose that the definite diagnosis of an MTrP requires a hypersensitive spot potentially felt as a nodule located within a taut band in addition to either referred pain, a local twitch response or at least two complementary diagnostic criteria, whereby signs of muscular dysfunction take on greater importance.

High Temporal Summation of Pain Predicts Immediate Analgesic Effect of Acupuncture in Chronic Pain Patients-A Prospective Cohort Study.

Objectives: This prospective cohort study explored whether two distinguished sensory parameters predicted acupuncture effects in chronic pain patients; namely high temporal summation of pain (TS) indicating spinal synaptic facilitation as well as a low vibration detection threshold (VDT) indicating a loss of Aß-fiber function. Methods: Pinprick induced TS and VDT were assessed by standardized, validated methods at the most painful body site and a pain free control site in 100 chronic pain patients receiving six acupuncture sessions as part of an interdisciplinary multimodal pain treatment (IMPT). Immediate change in pain intensity after the first acupuncture session (first treatment on the first day of IMPT) was assessed by the verbal rating scale (VRS, 0-100). After 4 weeks of treatment, patients indicated in a questionnaire whether acupuncture had relieved pain immediately and whether it had contributed to overall pain reduction and well-being after IMPT. Results: Logistic regression analysis revealed an association between high TS at the control site and a reduction in pain intensity of at least 30% (VRS) after the first acupuncture (OR [95%-CI] 4.3 [1.6-11.8]). Questionnaire ratings of immediate pain relief after acupuncture were associated with high TS at the control site (OR [95%-CI] 3.8 [1.4-10.2] any pain relief, OR [95%-CI] 5.5 [1.7-17.1] over 50% pain reduction) and at the pain site (OR [95%-CI] 3.2 [1.2-8.9] any pain relief). Appraisals of the contribution of acupuncture to overall pain reduction and well-being after IMPT were not associated with TS. The VDT was not associated with any outcome. Conclusion: This explorative study provides first-time evidence that high TS, especially at a pain free control site, but not VDT, might predict immediate analgesic response to acupuncture in chronic pain patients. Thus, highly centrally sensitized chronic pain patients might respond particularly well to acupuncture.

Quality of postoperative pain management in Ethiopia: A prospective longitudinal study.

BACKGROUND: The annual number of surgical operations performed is increasing throughout the world. With this rise in the number of surgeries performed, so too, the challenge of effectively managing postoperative pain. In Africa, there are scanty data available that make use of multi-center data to characterize the quality of postoperative pain management. In this study using a longitudinal data, we have attempted to characterize the quality of postoperative pain management; among patients scheduled for major elective orthopedic, gynecologic and general surgery. METHODS: This prospective longitudinal study evaluated the quality of postoperative pain management in patients undergoing elective general, gynecologic, and orthopedic surgery. We quantified the prevalence of moderate to severe postoperative pain with the International Pain Outcome Questionnaire and the corresponding adequacy of treatment with the pain management index. At four time points after surgery, we estimated pain severity, its physical and emotional interference, and patient satisfaction. RESULTS: Moderate to severe postoperative pain was present in 88.2% of patients, and pain was inadequately treated in 58.4% of these patients. Chronic pain (ß = 0.346, 95% CI: 0.212, 0.480) predicted patients' worst pain intensity. Gender was not associated with the worst pain intensity or percentage of time spent in severe pain. Patient's pain intensity did not predicted the level of satisfaction. CONCLUSIONS: The prevalence of moderate to severe postoperative pain and its functional interference is high in Ethiopian patients. The treatment provided to patients is inadequate and not in line with international recommendations and standards.

The views of patients, healthcare professionals and hospital officials on barriers to and facilitators of quality pain management in Ethiopian hospitals: A qualitative study.

BACKGROUND: Postoperative pain remains a challenge in the developed world, but the consequences of inadequately treated postoperative pain are particularly severe in low- and middle-income countries. Since 2011, reports have drawn attention to the poor quality of postoperative pain management in Ethiopia; however, our multicenter qualitative study was the first to attempt to understand the factors that are barriers to and facilitators of quality pain managment in the country. To this aim, the study explored the perspectives of patients, healthcare professionals, and hospital officials. We expected that the results of this study would inform strategies to improve the provision of quality pain management in Ethiopia and perhaps even in other low- and middle-income countries. METHODS: This study used a qualitative, descriptive approach in which nine healthcare professionals, nine patients, and six hospital officials (i.e. executives in a managerial or leadership position in administration, nursing, or education) participated in face-to-face, semi-structured interviews. Thematic data analysis was conducted, and patterns were explained with the help of a theoretical framework. FINDINGS: The barriers identified ranged from healthcare professionals' lack of empathy to a positive social appraisal of patients' ability to cope with pain. They also included a lack of emphasis on pain and its management during early medical education, together with the absence of available resources. Enhancing the ability of healthcare professionals to create favorable rapport with patients and increasing the cultural competence of professionals are essential ingredients of future pain education interventions. CONCLUSIONS: Barriers to and facilitators of postoperative pain management do not exist independently but are reciprocally linked. This finding calls for holistic and inclusive interventions targeting healthcare professionals, patients, and hospital officials. The current situation is unlikely to improve if only healthcare professionals are educated about pain physiology, pharmacology, and management. Patients should also be educated, and the hospital environment should be modified to provide high-quality postoperative pain management.

Somatosensory profiles in acute herpes zoster and predictors of postherpetic neuralgia.

This prospective cohort study aimed to characterize the sensory profile during acute herpes zoster (AHZ) and to explore sensory signs as well as physical and psychosocial health as predictors for postherpetic neuralgia (PHN). Results of quantitative sensory testing of 74 patients with AHZ at the affected site and at the distant contralateral control site were compared to a healthy control group. Pain characteristics (Neuropathic Pain and Symptom Inventory and SES), physical functioning, and psychosocial health aspects (Pain Disability Index, SF-36, and STAI) were assessed by questionnaires. Patients with PHN (n = 13) at 6-month follow-up were compared to those without PHN (n = 45). Sensory signs at the affected site were thermal and vibratory hypesthesia, dynamic mechanical allodynia (DMA), pressure hyperalgesia, and high wind-up (18%-29%), as well as paradoxical heat sensations and pinprick hypalgesia (13.5%). The unaffected control site exhibited thermal and vibratory hypesthesia, DMA, and pressure hyperalgesia. Dynamic mechanical allodynia and pinprick hypalgesia were mutually exclusive. Postherpetic neuralgia was associated with DMA (38.5% vs 6.7%; P = 0.010) and vibratory hypesthesia (38.5% vs 11.1%; P = 0.036) at the control site, with mechanical gain and/or loss combined with normal thermal detection (affected site: 69.2% vs 31.1%; P = 0.023; control site: 53.8% vs 15.5%; P = 0.009). Pain Disability Index (P = 0.036) and SES affective pain perception scores (P = 0.031) were over 50% higher, and 6 of 8 SF-36 subscores were over 50% lower (P < 0.045) in PHN. Sensory profiles in AHZ indicate deafferentation and central but not peripheral sensitization. Sensory signs at distant body sites, strong affective pain perception, as well as reduced quality of life and physical functioning in the acute phase may reflect risk factors for the transition to PHN.

Acupuncture-induced changes of pressure pain threshold are mediated by segmental inhibition--a randomized controlled trial.

Our aim was to distinguish between spinal and supraspinal mechanisms in the intact nervous system by comparing homosegmental and heterosegmental effects of electroacupuncture (EA) and manual acupuncture (MA) on sensory perception in healthy volunteers by means of quantitative sensory testing. Seventy-two healthy volunteers were randomly assigned to receive either MA or EA at SP 6, SP 9, GB 39, and ST 36 at the left leg or relaxed for 30 minutes (control group [CG]). Blinded examiners assessed 13 sensory modalities (thermal and mechanical detection and pain thresholds) at the upper arms and lower legs before and after intervention by means of a standardized quantitative sensory testing battery. Change scores of all 13 sensory thresholds were compared between groups. The main outcome measure was the change score of the pressure pain threshold (PPT). There were no baseline differences between groups. Pressure pain threshold change scores at the lower left leg, in the same segment as the needling site, differed significantly (P = 0.008) between the EA (median: 103.01 kPa) and CG groups (median: 0.00 kPa) but not between the MA (median: 0.00 kPa) and CG groups. No further significant change score differences were found between one of the acupuncture groups and the CG. The PPT can be changed by EA. The PPT increase was confined to the segment of needling, which indicates that it is mainly mediated by segmental inhibition in the spinal cord. This underscores the importance of segmental needling and electrical stimulation in clinical practice.

Effects of acupuncture on sensory perception: a systematic review and meta-analysis.

BACKGROUND: The effect of acupuncture on sensory perception has never been systematically reviewed; although, studies on acupuncture mechanisms are frequently based on the idea that changes in sensory thresholds reflect its effect on the nervous system. METHODS: Pubmed, EMBASE and Scopus were screened for studies investigating the effect of acupuncture on thermal or mechanical detection or pain thresholds in humans published in English or German. A meta-analysis of high quality studies was performed. RESULTS: Out of 3007 identified articles 85 were included. Sixty five studies showed that acupuncture affects at least one sensory threshold. Most studies assessed the pressure pain threshold of which 80% reported an increase after acupuncture. Significant short- and long-term effects on the pressure pain threshold in pain patients were revealed by two meta-analyses including four and two high quality studies, respectively. In over 60% of studies, acupuncture reduced sensitivity to noxious thermal stimuli, but measuring methods might influence results. Few but consistent data indicate that acupuncture reduces pin-prick like pain but not mechanical detection. Results on thermal detection are heterogeneous. Sensory threshold changes were equally frequent reported after manual acupuncture as after electroacupuncture. Among 48 sham-controlled studies, 25 showed stronger effects on sensory thresholds through verum than through sham acupuncture, but in 9 studies significant threshold changes were also observed after sham acupuncture. Overall, there is a lack of high quality acupuncture studies applying comprehensive assessments of sensory perception. CONCLUSIONS: Our findings indicate that acupuncture affects sensory perception. Results are most compelling for the pressure pain threshold, especially in pain conditions associated with tenderness. Sham acupuncture can also cause such effects. Future studies should incorporate comprehensive, standardized assessments of sensory profiles in order to fully characterize its effect on sensory perception and to explore the predictive value of sensory profiles for the effectiveness of acupuncture.

Acupuncture for post anaesthetic recovery and postoperative pain: study protocol for a randomised controlled trial.

BACKGROUND: We report on the design and implementation of a study protocol entitled Acupuncture randomised trial for post anaesthetic recovery and postoperative pain - a pilot study (ACUARP) designed to investigate the effectiveness of acupuncture therapy performed in the perioperative period on post anaesthetic recovery and postoperative pain. METHODS/DESIGN: The study is designed as a randomised controlled pilot trial with three arms and partial double blinding. We will compare (a) press needle acupuncture, (b) no treatment and (c) press plaster acupressure in a standardised anaesthetic setting. Seventy-five patients scheduled for laparoscopic surgery to the uterus or ovaries will be allocated randomly to one of the three trial arms. The total observation period will begin one day before surgery and end on the second postoperative day. Twelve press needles and press plasters are to be administered preoperatively at seven acupuncture points. The primary outcome measure will be time from extubation to 'ready for discharge' from the post anaesthesia care unit (in minutes). The 'ready for discharge' end point will be assessed using three different scores: the Aldrete score, the Post Anaesthetic Discharge Scoring System and an In-House score. Secondary outcome measures will comprise pre-, intra- and postoperative variables (which are anxiety, pain, nausea and vomiting, concomitant medication). DISCUSSION: The results of this study will provide information on whether acupuncture may improve patient post anaesthetic recovery. Comparing acupuncture with acupressure will provide insight into potential therapeutic differences between invasive and non-invasive acupuncture techniques. TRIAL REGISTRATION: NCT01816386 (First received: 28 October 2012).